This week on TV, Walter Bishop is back, and he's cooking up some surprises. Also back? Supernatural's Castiel. And Thundercats. And Mythbusters. On Once Upon a Time, the Who's Roger Daltrey plays a talking caterpillar in Wonderland.

Plus you know the Marvel movies will never give you an Iron Man-Magneto showdown — but you can watch part of one right here, right now. Plus we've got clips from Supernatural, Alcatraz, Vampire Diaries, and other shows. Television is bursting with wonders this week.

Today:

Alcatraz (9 PM, FOX):
This show has been showing a noticeable uptick in quality the past couple of weeks — so this week's episode is bound to be something special as well, right? Or else, it could be about a sweet violin-playing inmate (Rami Malek) who murders women in their lingerie. Yawn. At least it sounds like Webb Porter's blood could be what brings Dr. Sangupta back to life. Witness a sneak peek!

Being Human (9 PM, Syfy):
We're still dealing with the Reaper/Sally standoff, and this time the Reaper imprisons Sally in a dream world. Let's hope the dream world looks just like Deep Space Nine and all the figments of Sally's consciousness are represented by Colm Meaney and Andrew Robinson.

Also tonight: a brand new (to Americans) episode of Lost Girl at 10 PM on Syfy. Plus a dance-themed episode of Castle.

Tuesday:

The River (9 PM, ABC):
It's the season finale, following on from last week's ultra-surprising episode in which they actually, you know, found the guy they were looking for. And this week, a member of their crew is shot dead, and this causes Jahel to summon the Boiuna to help, against her father's wishes. Let's hope there's some satisfying resolution here, since this show might not be coming back.

Science Special: Alien Encounters: The Arrival (10 PM, Science):
Another one of Science's recent specials in which they try to capitalize on the popularity of Ancient Aliens and Modern Aliens and the ever-popular Postmodern Aliens. This time: Aliens are showing up, and you can learn how to greet them.

Also on TV tonight: Another Unforgettable, the show about the woman with the mutant super-brain, on CBS at 10 PM.

Wednesday:

Voltron Force and Iron Man: Armored Adventures (8 PM, NickToons):
On Voltron Force, Vince's latest prototype brain interface tiara thingy may have a serious effect on Daniel. But more importantly, on Iron Man: Armored Adventures, Tony faces off against Magneto! Yes, Magneto is allowed to show up on a non-X-Men cartoon. Check out the first clip of the Iron Man-Magneto smackdown right here.

South Park and Ugly Americans (10 PM, Comedy Central):
No clue what South Park is about this week. On Ugly Americans, "Randall's powerful new arm gets him a job at the Department of Integration, which needs a ringer for a big intramural football game; and the move could send Mark to the second string."

Thursday:

Community (8 PM, NBC):
Enjoy it while it lasts! I can't really explain what happens in this episode better than the official synopsis:

As the study group returns after winter break, Jeff (Joel McHale) reveals that he's been seeing a shrink and he's on anti-anxiety medication. The newfound confidence leads him to experience debilitating levels of narcissism, which Britta (Gillian Jacobs) tries to help him manage. Meanwhile, over the break, Abed (Danny Pudi) developed a celebrity impersonator habit that has saddled him with debt. In order to help Abed shed his debt, the study group dons costumes and goes to work for Vincent (French Stewart, "3rd Rock from the Sun," "The Muppets") as celebrity impersonators - appearing in character at a Bar Mitzvah celebration.

The Vampire Diaries (8 PM, The CW):
Sage, the awesome boxing lady we met in the 1912 flashbacks last week, is turning up in the present day. Huzzah! Here's the synopsis:

A century after their first encounter, Damon (Ian Somerhalder) and Sage (guest star Cassidy Freeman) meet again at the ceremony to kick-off the restoration of Wickery Bridge. Damon is surprised to learn the reason Sage has returned, and pleased when she devises an unusual method to help him figure out what Rebekah (guest star Claire Holt) is up to. Abby (guest star Persia White) is having a hard time adjusting to her new reality, despite Bonnie (Kat Graham) and Caroline's (Candice Accola) efforts to help. When Damon informs Elena (Nina Dobrev) of Stefan's (Paul Wesley) latest struggles, she reaches out to Stefan to help her save a friend in danger, in hopes that it will help bring Stefan even closer to his humanity. Finally, when Damon discovers a new secret weapon, he lets Stefan in on the news.

Here's your first clip. That's followed by a new Secret Circle, in which Cassie deals with her evil dad. Or doesn't, as the case may be.

Touch (9 PM, FOX):
At last, it's the second episode of Fox's new "autistic superkid" show, which aired its pilot a couple of months ago. This time Kiefer Sutherland's mute 11-year-old kid leads him to a pawn shop, where a robbery is linked to a visiting flight attendant, a grieiving visitor from India who's scattering his father's ashes, a magician in Moscow, a cancer patient and a mobster. The episode's title? "1+1=3", which might sum up this show's zany approach to logic. You have to love a show where Danny Glover can say with a straight face, "He sees the entire universe."

Tonight sees the launch of Touch, Kiefer Sutherland's show about a father whose…
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Awake (10 PM, NBC):
Speaking of fathers and sons and psychologists spouting off, this show is back with an episode where Michael Britten meets his son's former babysitter Kate in two different contexts. In one universe, she's a witness to an alleged suicide aboard a yacht. In the other universe, she's a murder suspect.

Archer (10 PM, FX):
It's the season finale! In "Space Race, Part II," Archer and his team try to prevent catastrophe aboard the International Space Station, and they wish they'd never journeyed to the final frontier. And it looks like Archer gets a heroic "power loader" scene, a la Aliens.

Ben 10: Destroy All Aliens turns the clock back to 10-year-old Ben Tennyson, fresh off his heroic summer vacation with the Omnitrix, as he struggles with detention, homework, and being grounded by his parents. Desperate times call for desperate measures as Ben jumps at the chance to escape from it all and into the Total Alien Immersion training program on the far side of the galaxy. But before he can even leave Earth's orbit, Ben's ship is attacked and he is sent crashing back to Earth stuck in his alien forms and battling a very hostile Mecamorph warrior.

Fringe (9 PM, FOX):
Thank goodness, the only mad scientist on television is back to keep us all sane. Seriously, thank the sky weasels. This episode, "A Short Story About Love," is one that the show's producers have been talking up for ages, and it seems like they're pretty proud of it — so fingers crossed. A serial killer is targeting love, while meanwhile Peter tries to untangle his latest Peter/Olivia/Olivia love triangle.

Supernatural (9 PM, The CW):
Speaking of people being back, this episode finally sees the return of Castiel, and maybe this show can get a decent boost from the awesome powers of Misha Collins. Plus this episode was written by all-time MVP and showrunner Sera Gamble. Lucifer finally puts Sam into a mental institution, and Dean is desperate to save his brother — so he calls every hunter he knows, until one of them puts him in touch with a healer who turns out to be a familiar face. Here's a sneak peek!

Also at 10 PM Friday: Ancient Aliens on H2, and a new (to Americans) episode of Merlin on Syfy.

Saturday:

Thundercats and other stuff (9 AM, Cartoon Network):
Cartoon Network continues to move all of its biggest programming from Friday evening to Saturday morning. At 9 AM, Ben 10 Week continues with a new episode of Ben 10: Ultimate Alien, "The Ultimate Enemy, Part 1." And then at 9:30 AM, there's a brand new Thundercats — the first new episode in the U.S. in three months. Then at 10, there's an hour of DC Nation, including Green Lantern, Young Justice and totally random/silly short subjects.

Fluttershy needs to overcome her self-consciousness in order to help Rainbow Dash and the other pegasi with the Rainy Season.

Being Human (9 PM, BBC America):
Vampire Adam has a new girlfriend — and she's a succubus! Yes, this show is branching out. Yvonne gives strange erotic dreams to Tom and Hal, and we'll see just how much of those can appear on BBC America without cuts.

Sunday:

Frozen Planet (8 PM, Discovery):
Here's what to expect from this week's outing of the BBC/Discovery series about the polar regions:

It is high summer in the polar regions, and the sun never sets. Vast hordes of summer visitors cram a lifetime of drama into one long, magical day; they must feed, fight and rear their young in this brief window of plenty. Summer is a tough time for the polar bear family, as their ice world melts away and the cubs take their first swimming lesson. Some bears save energy by dozing on icy sun beds, while others go egg-collecting in an Arctic tern colony, braving bombardment by sharp beaks. There are even bigger battles on the tundra; a herd of musk oxen gallop to the rescue as a calf is caught in a life and death struggle with a pair of Arctic wolves. But summer also brings surprises, as a huge colony of 400,000 king penguins cope with an unlikely problem - heat. The adults go surfing, while the woolly-coated chicks take a cooling mud bath. Nearby, a bull fur seal is prepared to fight to the death with a rival. Fur flies as the little pups struggle desperately to keep out of the way of the duelling giants. Further south, a minke whale is hunted amongst the ice floes by a family of killer whales. The dramatic chase lasts over 2 hours and has never been filmed before. The killers harry the minke whale, taking it in turns to wear it down. Eventually it succumbs to the relentless battering. Finally, comical adelie penguins waddle back to their half a million strong colony like clockwork toys. The fluffy chicks need constant feeding and protection as piratical skuas patrol the skies. When an unguarded chick is snatched, a dramatic "dogfight" ensues.

Once Upon a Time (8 PM, ABC):
This is the long-awaited episode — long-awaited by all reasonable people, in any case — in which Roger Daltrey from the Who guest stars as the voice of a talking caterpillar. Plus Bucky Barnes himself, Sebastian Stan, as the Mad Hatter. Just when you thought this show couldn't get more insane. Here's what's going on:

While searching for a missing Mary Margaret, Emma is kidnapped by a man whose affinity for hats has him teetering on the edge of madness. Meanwhile, viewers will be transported outside of the fairytale land that was for the first time when the Evil Queen persuades a skillful man of magic to come work for her one last time and travel to Wonderland in order to help steal something from the Queen of Hearts.

Mythbusters (9 PM, Discovery):
This show premieres a new season, in a new time slot, with "Duct Tape Island." Here's the whole gang, talking about the episode at San Diego Comic Con.